The killing happened on Thursday in what authorities believe was a robbery attempt.
She was last seen alive by a family member who lives on the second floor around 2:30 p.m. on Thursday. When the family member returned a few hours later they found Hempel on the floor of the living room unresponsive, said prosecutor Theodore J. Romankow.
She was pronounced dead at the scene at 6:21p.m.
The medical examiner ruled her death a homicide, but how she was killed has not been released.
A nearly life-long resident of the city Hempel was known in the neighborhood as a kind woman.
"Everyone deserves to feel safe in their home," said Romankow. "This is nothing but a senseless and brutal act against a defnelsess woman. As with all homicides we will use every available resource to make sure the killer is captured."
Congregants remembered Hempel Saturday at the regular Saturday mass at Blessed Sacrament Church in Elizabeth.
They said she never missed the 5:30 Saturday mass, walking to the church each week.
Union County Crime Stoppers is offering a reward of up to $5,000 for information that leads to the arrest and indictment of the person or people responsible for the homicide of Ms. Hempel. Anonymous calls may be placed to 908-654-TIPS or via the Internet at www.uctip.org.
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